Gene silencing of complement C5a receptor using siRNA for preventing ischemia/reperfusion injury

Ischemia/reperfusion (I/R) injury in organ transplantation significantly contributes to graft failure and is untreatable using current approaches. I/R injury is associated with activation of the complement system, leading to the release of anaphylatoxins, such as C5a, and the formation of the membrane attack complex. Here, we report a novel therapy for kidney I/R injury through silencing of the C5a receptor (C5aR) gene using siRNA. Mice were injected with 50 μg of C5aR siRNA 2 days before induction of ischemia. Renal ischemia was then induced through clamping of the renal vein and artery of the left kidney for 25 minutes. The therapeutic effects of siRNA on I/R were evaluated by assessment of renal function, histopathology, and inflammatory cytokines. siRNA targeting C5aR efficiently inhibited C5aR gene expression both in vitro and in vivo. Administering C5aR siRNA to mice preserved renal function from I/R injury, as evidenced by reduced levels of serum creatinine and blood urea nitrogen in the treated groups. Inhibition of C5aR also diminished in vivo production of the pro-inflammatory cytokine tumor necrosis factor-α and chemokines MIP-2 and KC, resulting in the reduction of neutrophils influx and cell necrosis in renal tissues. This study demonstrates that siRNA administration represents a novel approach to preventing renal I/R injury and may be used in a variety of clinical settings, including transplantation and acute tubular necrosis.     

Cysts of the pineal gland

Thirty-two cases of pineal cyst diagnosed by magnetic resonance imaging (MRI) were reviewed and are described. The pineal cyst was demonstrated to be an area with slightly less intensity than the surrounding tissue and with slightly greater intensity than the CSF on T1-weighted images. On the T2-weighted images this lesion was identified as a high-intensity area with smooth margins and was homogeneous in nature. In three cases presenting with headache, compression of the vein of Galen was identified, and compression of the quadrigeminal plate was demonstrated in five cases. No patients presented with both pineal and quadrigeminal lesions. Of the cases, 63% were not detected by CT scanning alone. There were two cases in which the cyst ruptured and collapsed spontaneously during follow-up. It is emphasized that the presence of this lesion, which was more frequent than previously expected, should be kept in mind when diagnosing pineal tumors and should not be misdiagnosed. Surgery should not be undertaken unless the lesion produces symptoms due to the compression of the quadrigeminal plate, aqueduct, or the vein of Galen.     

Congenital frontal bone defect with intact overlying scalp

An unusual case of a congenital frontal bone defect with intact overlying scalp and intact underlying dura mater is reported. Although spontaneous healing by the intact underlying dura mater by regeneration was expected, it did not occur. Cranioplasty was done for protective and cosmetic purposes. A review of the literature of congenital skull defects shows that spontaneous regeneration does not occur in this rare anomaly.     

Isolated dissection of the main trunk of the superior mesenteric artery

A 47-year-old male with sudden onset of abdominal pain was diagnosed as having a tight stenosis and a long irregular narrowing of the main trunk of the superior mesenteric artery (SMA), which induced transient ileus. The patient was successfully treated by a patch angioplasty using an autologous saphenous vein. An intraoperative finding revealed the isolated dissection of the SMA, and a histological examination confirmed the dissection of the SMA, in which false lumen was thrombosed.     

Antigen induced arthritis (AIA) can be transferred by bone marrow transplantation: evidence that interleukin 6 is essential for induction of AIA

OBJECTIVE: To investigate the role of bone marrow cells (BMC) in the induction of antigen induced arthritis (AIA), the expression of 3 major proinflammatory cytokines, interleukin 1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha), and IL-6, was examined in the bone marrow (BM) of mice with AIA. We also examined whether AIA could be transferred by bone marrow transplantation (BMT). METHODS: Expression of IL-1beta, TNF-alpha, and IL-6 in BMC was assessed by immunohistochemistry throughout the course of AIA. BMT experiments were performed using 2 different mouse genotypes, wild type (IL-6+/+) and IL-6 deficient (IL-6-/-) mice, as a donor. The gradation of AIA was evaluated histologically. RESULTS: IL-6 was highly expressed in the BM at induction as well as during progression of AIA, while TNF-alpha showed a marginal expression, and no significant expression of IL-1beta was detected throughout the course of AIA. In BMT experiments, all irradiated IL-6+/+ mice developed typical AIA by transplantation of BMC from immunized IL-6+/+ mice, whereas almost no irradiated IL- 6+/+ mice transplanted with BMC from the immunized IL-6-/- mice developed definite arthritis. CONCLUSION: These results suggest that BMC play a critical role and IL-6 is a key cytokine for the induction and progression of AIA. There may be clinical benefits in the blockade of IL-6 and BMT in the treatment of rheumatoid arthritis.     

Matrix metalloproteinase-9-dependent exposure of a cryptic migratory control site in collagen is required before retinal angiogenesis

Retinal neovascularization is a leading cause of human blindness. However, little is known concerning the molecular mechanisms controlling retinal neovascularization in vivo. Here we provide evidence that exposure of a collagen type IV cryptic epitope detected by monoclonal antibody (mAb) HUIV26, delineates sites of vascular bud formation and represents one of the earliest structural remodeling events required before vessel out-growth. Exposure of these cryptic sites was inhibited in matrix metalloproteinase (MMP)-9-deficient but not MMP-2-deficient mice implicating MMP-9 in their exposure. Retinal endothelial cell interactions with the HUIV26 epitopes induced endothelial cell migration, which was blocked by mAb HUIV26. Importantly, subcutaneous administration of mAb HUIV26 potently inhibited retinal angiogenesis in vivo. Taken together, these findings suggest a novel mechanism in which MMP-9 facilitates exposure of HUIV26 cryptic sites, thereby promoting retinal endothelial cell migration and neovascularization in vivo.     

Outcome of punctal plug occlusion therapy for severe dry eye syndrome

PURPOSE: Punctal occlusion using a silicone plug is one way of treating tear-deficient dry eye and it has been reported to be effective. We studied the outcome of punctal plug occlusion therapy for severe dry eye syndrome at our dry eye clinic. SUBJECTS AND METHODS: Subjects were 76 eyes of 51 patients [6 eyes of 5 males, 70 eyes of 46 females, mean age: 58.6 +/- 13.4 (mean +/- standard deviation), 49 eyes of 30 patients with Sj?gren's syndrome, 27 eyes of 21 patients without Sj?gren's syndrome] with severe tear-deficient dry eye who underwent punctal occlusion using a silicone plug (Punctal plug, FCI Co. Ltd, France) during the period of Nov. 1996 to Mar. 2000 at our dry eye clinic. They were under observation for 632 +/- 405 days (mean +/- standard deviation). We studied if there is difference in tolerance between the sizes of punctal plug, compared epithelial damage before and after plug insertion, and studied relief in symptoms using self-assessment. RESULTS: In tolerance of punctal plugs, 55.9% of all plugs were lost during our follow up, but there was no difference in time to loss between the sizes. Epithelial damage was reduced (p < 0.001). Dryness was the most reduced symptom: 26 patients (79%) got better, and only epiphora was increased, with 12 patients (36%) complaining slightly. CONCLUSION: Punctal plug occlusion therapy for tear-deficient dry eye is conclusively very effective.     

Association of preoperative photoreceptor displacement and improved central scotoma after idiopathic macular hole surgery

OBJECTIVE: To investigate the relationship between preoperative photoreceptor displacement and postoperative scotoma after unilateral idiopathic macular hole surgery. DESIGN: Prospective nonrandomized comparative self-controlled trial. PARTICIPANTS: Twenty patients who underwent successful surgery for unilateral idiopathic macular hole participated in the study. METHODS: Kinetic perimetry using red and green filter glasses, black binocular fixation targets, and red and green selective monocular stimuli was performed preoperatively. Scanning laser ophthalmoscope (SLO) microperimetry was performed preoperatively and postoperatively. RESULTS: Sixteen patients had photoreceptor displacement preoperatively. In preoperative SLO microperimetry, all eyes with a macular hole had a scotoma; postoperatively, 12 of 16 had no scotoma. All four eyes with no preoperative photoreceptor displacement were noted to have a postoperative scotoma. The prevalence of postoperative scotoma in patients with preoperative photoreceptor displacement (4 of 16; 25%) was significantly lower than that in patients without preoperative photoreceptor displacement (4 of 4; 100%) (P = 0.03). CONCLUSIONS: The presence or absence of photoreceptor displacement preoperatively should affect postsurgical visual function. Photoreceptor damage may occur in eyes without photoreceptor displacement preoperatively, resulting in scotoma postoperatively.     

p38 MAPK phosphorylation and NF-kappa B activation in human crescentic glomerulonephritis.

BACKGROUND: p38 mitogen-activated protein kinase (p38 MAPK) followed by the activation of NF-kappa B participates in the intracellular signal transduction and production of cytokines and chemokines. The pathophysiological roles of p38 MAPK and NF-kappa B in human glomerulonephritis, however, remain to be investigated. METHODS: We investigated the phosphorylated p38 MAPK (p-p38 MAPK) and activated NF-kappa B immunohistochemically in the kidneys of 34 patients with crescentic glomerulonephritis and 26 control patients with thin basement membrane disease and minimal change nephrotic syndrome. We also explored the co-localization of p-p38 MAPK with CCR5, the signal of which leads to p38 MAPK activation. Furthermore, urinary levels of MIP-1 alpha, the cognate ligand for CCR5, were determined by enzyme-linked immunosorbent assay. RESULTS: p-p38 MAPK-positive cells and activated NF-kappa B-positive cells were mainly detected in crescentic lesions, tubular epithelial cells, and interstitial mononuclear infiltrates. The number of p-p38 MAPK-positive cells in patients with crescentic glomerulonephritis was higher than that in control patients. The number of p-p38 MAPK-positive cells in glomeruli was well correlated with the percentage of cellular crescents, the number of CD68-positive cells, and urinary MIP-1 alpha levels. In addition, the number of activated NF-kappa B-positive cells was well correlated with the number of p-p38 MAPK-positive cells in glomeruli. Dual staining revealed that most of CCR5-positive cells were positive for p-p38 MAPK. Finally, p-p38 MAPK-positive cells and activated NF-kappa B-positive cells decreased during glucocorticoid therapy-induced convalescence. CONCLUSIONS: We conclude that the phosphorylation of p38 MAPK associated with the activation of NF-kappa B may be involved in the upregulation of intrarenal MIP-1 alpha and the utilization of CCR5 signalling, which may result in human crescentic glomerulonephritis.